This International Standard describes the free, mechanical impedance of the human male hand-arm system at the driving point. Values of the free impedance, expressed as modulus and phase, are provided for three orthogonal, translatory directions of excitation that correspond to the X_h, J_h and Z_h axes of the basicentric coordinate system for the hand defined in IS0 5349 and IS0 8727. The X_h, y_h and Z_h components of free impedance are defined as a function of frequency, from 10 Hz to 500 Hz, for specified arm positions, grip and feed forces, handle diameters, and intensities of excitation. The components of free impedance in the three directions are treated as being independent (see annex F).

This International Standard may be used to define typical values of the free, mechanical impedance of the hand-arm system at the driving point, applicable to males under the circumstances specified. For each impedance component, the free impedance is defined at each frequency by three values, to reflect the range of values measured on male hands. The upper and lower values define the range of most probable values of impedance. The middle value represents an overall mean of the human data, and defines the target value for all applications. This International Standard may be provisionally applied to females.

Reference values of the free, mechanical impedance at the driving point are provided as a function of frequency for a specified grip and feed force in annex A. These impedance values are intended for the determination of the transmissibility of resilient materials, when loaded by the hand-arm system.

Mathematical representations of the hand-arm system that model the values of free impedance are also provided in annexes C to E.